882 resultados para Life history calendar


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One of the main goals in current evolutionary biology research is to identify genes behind adaptive phenotypic variations. The advances in genomic technologies have made it possible to identify genetic loci behind these variations, also concerning non-model species. This thesis investigates the genetics of the behaviour and other adaptive traits of the nine-spined stickleback (Pungitius pungitius) through the application of different genetic approaches. Fennoscandian nine-spined stickleback populations express large phenotypical differences especially in behaviour, lifehistory traits and morphology. However the underlying genetic bases for these phenotypical differences have not been studied in detail. The results of the project will lay the foundation for further genetics studies and provide valuable information for our understanding of the genetics of the adaptive divergence of the nine-spined stickleback. A candidate gene approach was used to develop microsatellite markers situating close to candidate genes for behaviour in the nine-spined stickleback. Altogether 13 markers were developed and these markers were used in the subsequent studies with the anonymous random markers and physiologically important gene markers which are already currently available for nine-spined sticklebacks. It was shown that heterozygosity correlated with behaviour in one of the marine nine-spined stickleback populations but with contrasting effects: correlations with behaviour were negative when using physiological gene markers and positive with random markers. No correlation was found between behavioural markers and behaviour. From the physiological gene markers, a strong correlation was found between osmoregulation-related gene markers and behaviour. These results indicate that both local (physiological) and general (random) effects are important in the shaping of behaviour and that heterozygosity– behaviour correlations are population dependent. In this thesis a second linkage map for nine-spined sticklebacks was constructed. Compared to the earlier nine-spined stickleback linkage map, genomic rearrangements were observed between autosomal (LG7) and sex-determing (LG12) linkage groups. This newly constructed map was used in QTL mapping studies in order to locate genomic regions associated with pelvic structures, behaviour and body size/growth. One major QTL was found for pelvic structures and Pitx1 gene was related to these traits as was predicted from three-spined stickleback studies, but this was in contrast to earlier nine-spined stickleback study. The QTL studies also revealed that behaviour and body size/growth were genetically more complex by having more QTL than pelvic traits. However, in many cases, pelvic structure, body size/growth and behaviour were linked to similar map locations indicating possible pleiotropic effects of genes locating in these QTL regions. Many of the gene related markers resided in the QTL area. In the future, studying these possible candidate genes in depth might reveal the underlying mechanism behind the measured traits.

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Traditionally biologists have often considered individual differences in behaviour or physiology as a nuisance when investigating a population of individuals. These differences have mostly been dismissed as measurement errors or as non-adaptive variation around an adaptive population mean. Recent research, however, challenges this view. While long acknowledged in human personality studies, the importance of individual variation has recently entered into ecological and evolutionary studies in the form of animal personality. The concept of animal personality focuses on consistent differences within and between individuals in behavioural and physiological traits across time and contexts and its ecological and evolutionary consequences. Nevertheless, a satisfactory explanation for the existence of personality is still lacking. Although there is a growing number of explanatory theoretical models, there is still a lack of empirical studies on wild populations showing how traditional life-history tradeoffs can explain the maintenance of variation in personality traits. In this thesis, I first investigate the validity of variation in allostatic load or baseline corticosterone (CORT) concentrations as a measure for differences in individual quality. The association between CORT and quality has recently been summarised under the “CORT-fitness hypothesis”, which states that a general negative relationship between baseline CORT and fitness exists. I then continue to apply the concept of animal personality to depict how the life-history trade-off between survival and fecundity is mediated in incubating female eiders (Somateria mollissima), thereby maintaining variation in behaviour and physiology. To this end, I investigated breeding female eiders from a wild population that breeds in the archipelago around Tvärminne Zoological Station, SW Finland. The field data used was collected from 2008 to 2012. The overall aim of the thesis was to show how differences in personality and stress responsiveness are linked to a life-history context. In the four chapters I examine how the life-history trade-off between survival and fecundity could be resolved depending on consistent individual differences in escape behaviour, stress physiology, individual quality and nest-site selection. First, I corroborated the validity of the “CORT-fitness hypothesis”, by showing that reproductive success is generally negatively correlated with serum and faecal baseline CORT levels. The association between individual quality and baseline CORT is, however, context dependent. Poor body condition was associated with elevated serum baseline CORT only in older breeders, while a larger reproductive investment (clutch mass) was associated with elevated serum baseline CORT among females breeding late in the season. Interestingly, good body condition was associated with elevated faecal baseline CORT levels in late breeders. High faecal baseline CORT levels were positively related to high baseline body temperature, and breeders in poor condition showed an elevated baseline body temperature, but only on open islands. The relationship between stress physiology and individual quality is modulated by breeding experience and breeding phenology. Consequently, the context dependency highlights that this relationship has to be interpreted cautiously. Additionally, I verified if stress responsiveness is related to risk-taking behaviour. Females who took fewer risks (longer flight initiation distance) showed a stronger stress response (measured as an increase in CORT concentration after capture and handling of the bird). However, this association was modulated by breeding experience and body condition, with young breeders and those in poor body condition showing the strongest relationship between risktaking and stress responsiveness. Shy females (longer flight initiation distance) also incubated their clutch for a shorter time. Additionally, I demonstrated that stress responsiveness and predation risk interact with maternal investment and reproductive success. Under high risk of predation, females that incubated a larger clutch showed a stronger stress response. Surprisingly, these females also exhibited higher reproductive success than females with a weaker stress response. Again, these context dependent results suggest that the relationship between stress responsiveness and risk-taking behaviour should not be studied in isolation from individual quality and that stress responsiveness may show adaptive plasticity when individuals are exposed to different predation regimes. Finally, female risk-taking behaviour and stress coping styles were also related to nest-site choice. Less stress responsive females more frequently occupied nests with greater coverage that were farther away from the shoreline. Females nesting in nests with medium cover and farther from the shoreline had higher reproductive success. These results suggest that different personality types are distributed non-randomly in space. In this thesis I was able to demonstrate that personalities and stress coping strategies are persistent individual characteristics, which express measurable effects on fitness. This suggests that those traits are exposed to natural selection and thereby can evolve. Furthermore, individual variation in personality and stress coping strategy is linked to the alternative ways in which animals resolve essential life-history trade-offs.

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I studied the associations between migration-related physiological regulation (corticosterone) and body condition of barn swallows (Hirundo rustica L.). An additional purpose was to determine whether oxidative stress and biotransformation activity vary seasonally. Since physiological regulation, biotransformation activity and the stress involved may be important factors for body condition during migration; they may have direct effects on migration success. This in turn may influence other important life history stages, such as breeding and moult. In the thesis I used barn swallow data of the Finnish Ringing Centre (1997–2009), consisting of all juveniles ringed in the nests and recaptured from night roosts later the same autumn. Before the autumn migration in Finland I also captured, ringed and sampled barn swallows from night roosts in 2003, 2006, 2007 and 2011. Samples preceding spring migration in South Africa were collected in 2007. Juvenile barn swallows started to migrate southward in mid-August (first broods). Second broods started their migration at a younger age and almost a month later than first broods (mid-September). Barn swallows increased body mass and accumulated fat for the autumn migration. In the course of the autumn they seemed to be able to prevent the loss of energy already accumulated, since the proportional overnight mass loss, fat loss and faecal production decreased. Surprisingly, corticosterone, the major energy-regulating hormone in birds, seemed not to be involved in the fuelling process. Previous studies with warblers, sparrows and shorebirds had shown that during migration, the baseline levels of corticosterone were elevated in order to facilitate fuelling. It is possible that for Finnish barn swallows the most important fuelling place is in southern Europe, since northern and eastern populations migrate via the Balkan Peninsula. However, the adrenocortical stress response of Finnish barn swallows in good body condition was lower than that of those in poor body condition. Birds clearly suppressed the response, probably to prevent the catabolic effects of excessive corticosterone levels; birds cannot afford to lose muscle mass before migration. South African barn swallows had high levels of baseline corticosterone, but this may have been associated with the high oxidative damage and biotransformation activity of those birds. Barn swallows in spring and summer had low biotransformation activity and intermediate oxidative stress, which was probably related to breeding. Autumn birds had low biotransformation activity and oxidative stress but high redox enzyme activities in some migration-related enzymes.

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(Monostromatic green algae (Ulvales, Chlorophyta) of São Paulo and Paraná states (Brazil): distribution, growth, and reproduction). Culture studies were used for taxa identification and to understand aspects of the biology and physiology of monostromatic green blades growing in various sites along the coast of São Paulo state (23º30'-25ºl2'S, 45º10'-48ºW) and one site in Paraná state (25º35'S, 48º21'W), southeast and south Brazil, respectively. Possible variations of the growth rate, age of reproduction and life history were tested under different conditions of temperature, salinity and day length. Two species were found: Ulvaria oxysperma (Kützing) Bliding and Monostroma sp. The first one has been previously reported for many temperate and tropical estuaries around the world. Green monostromatic blades with the same life-history and ontogeny as Monostroma sp. have been reported so far only for the tropical coast of Brazil. Species are distinct in their ontogeny of the thallus (constant under different conditions) and limiting temperatures of survival. U. oxysperma grows and reproduces from 10 to 25ºC and dies when maintained at 30ºC; Monostroma sp. does not reproduce at 15ºC and survives at 30ºC. The different salinities and day lengths that were tested had no significant effect on either species.

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(Gracilariales, Rhodophyta) é uma macroalga marinha de coloração vermelha (vm) comum na costa Nordeste do Brasil e amplamente coletada para a extração de ágar. O objetivo deste estudo foi completar o histórico de vida de espécimens selvagens (coloração vermelha) e variantes cromáticas. Duas variantes foram isoladas, além dos espécimens selvagens coletados na praia de Paracuru, Ceará: i, marrom-esverdeada (me), encontrada em uma população natural da praia de Paracuru; e ii, verde (vd), obtida espontaneamente in vitro a partir de um ramo tetrasporofítico. As condições gerais de cultivo tanto para gametófitos quanto para tetrasporófitos foram: meio de cultura von Stosch 25%; fotoperíodo 14L:10E (luz: escuro); irradiância 100 µm.m-2.s-1 e aeração a cada 30 min. Tetrasporófitos das três colorações e gametófitos verdes foram cultivados também em 10L:14E. O histórico de vida foi completado in vitro em 498 (vm), 523 (me) e 861 (vd) dias, mostrando-se do tipo Polysiphonia. Tetrasporófitos produziram tetrásporos apenas em fotoperíodo 10L:14E. Gametófitos femininos verdes desenvolveram cistocarpos apenas em fotoperíodo 14L:10E. No entanto, a diferenciação de conceptáculos do tipo verrucosa em gametófitos masculinos verdes e a liberação de espermácios ocorreu em ambos os fotoperíodos. Gametófitos masculinos vermelhos apresentaram conceptáculos espermatangiais do tipo henriquesiana, enquanto gametófitos masculinos marrom-esverdeados apresentaram os tipos verrucosa e henriquesiana. Não foram verificadas diferenças quanto ao hábito de espécimens de uma mesma coloração, independentemente do estádio reprodutivo analisado. Verificou-se em todos os tetrasporófitos a germinação de tetrásporos in situ.

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The poorly known Mimosa splendida Barneby has been rediscovered in the Chapada dos Veadeiros, Brazil, 105 years after its single record in 1895. Data on its habitat description, demography, reproductive parameters, and geographic range are presented. Preliminary results suggest that the rarity of M. splendida in herbarium collections is associated with a narrow geographic range, and a specialized habitat preference on rocky slopes.

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Reciprocal selection between interacting species is a major driver of biodiversity at both the genetic and the species level. This reciprocal selection, or coevolution, has led to the diversification of two highly diverse and abundant groups of organisms, flowering plants and their insect herbivores. In heterogeneous environments, the outcome of coevolved species interactions is influenced by the surrounding community and/or the abiotic environment. The process of adaptation allows species to adapt to their local conditions and to local populations of interacting species. However, adaptation can be disrupted or slowed down by an absence of genetic variation or by increased inbreeding, together with the following inbreeding depression, both of which are common in small and isolated populations that occur in fragmented environments. I studied the interaction between a long-lived plant Vincetoxicum hirundinaria and its specialist herbivore Abrostola asclepiadis in the southwestern archipelago of Finland. I focused on mutual local adaptation of plants and herbivores, which is a demonstration of reciprocal selection between species, a prerequisite for coevolution. I then proceeded to investigate the processes that could potentially hamper local adaptation, or species interaction in general, when the population size is small. I did this by examining how inbreeding of both plants and herbivores affects traits that are important for interaction, as well as among-population variation in the effects of inbreeding. In addition to bi-parental inbreeding, in plants inbreeding can arise from self-fertilization which has important implications for mating system evolution. I found that local adaptation of the plant to its herbivores varied among populations. Local adaptation of the herbivore varied among populations and years, being weaker in populations that were most connected. Inbreeding caused inbreeding depression in both plants and herbivores. In some populations inbreeding depression in herbivore biomass was stronger in herbivores feeding on inbred plants than in those feeding on outbred ones. For plants it was the other way around: inbreeding depression in anti-herbivore resistance decreased when the herbivores were inbred. Underlying some of the among-population variation in the effects of inbreeding is variation in plant phenolic compounds. However, variation in the modification of phenolic compounds in the digestive tract of the herbivore did not explain the inbreeding depression in herbivore biomass. Finally, adult herbivores had a preference for outbred host plants for egg deposition, and herbivore inbreeding had a positive effect on egg survival when the eggs were exposed to predators and parasitoids. These results suggest that plants and herbivores indeed exert reciprocal selection, as demonstrated by the significant local adaptation of V. hirundinaria and A. asclepiadis to one another. The most significant cause of disruption of the local adaptation of herbivore populations was population connectivity, and thus probably gene flow. In plants local adaptation tended to increase with increasing genetic variation. Whether or not inbreeding depression occurred varied according to the life-history stage of the herbivore and/or the plant trait in question. In addition, the effects of inbreeding strongly depended on the population. Taken together, inbreeding modified plant-herbivore interactions at several different levels, and can thus affect the strength of reciprocal selection between species. Thus inbreeding has the potential to affect the outcome of coevolution.

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Dignity is seen important in health care context but considered as a controversial and complex concept. In health care context, it is described as being influenced by for example autonomy, respect, communication, privacy and hospital environment. Patient dignity is related to satisfaction with care, reduced stress, better confidence in health services, enhanced patient outcomes and shorter stay in a hospital. Stroke patients may struggle for dignity as being dependent on other people has impact on the patients’ self-image. In all, stroke patients are very specific patient group and considered vulnerable from emotional aspect. Therefore study findings from other patient groups in the area of ethical problems cannot be transferred to the stroke patients. This master’s thesis consists of two parts. The first part is the literature review of patients’ dignity in hospital care. The literature defined dignity and described factors promoting and reducing it. The results were ambiguous and thus a clear understanding was not able to create. That was the basis for the second part of the master’s thesis, the empirical study. This part aimed to develop theoretical construction to explore the realization of stroke patients’ dignity in hospital care. The data of the second part was collected by interviewing 16 stroke patients and analyzed using the constant comparison of Grounded Theory. The result was ‘The Theory of Realization of Stroke Patients’ Dignity in Hospital Care’ which is described not only in this master’s thesis but also as a scientific article. The theory consists of the core category, four generic elements and five specific types on realization. The core category emerged as ‘dignity in a new situation’. After a stroke, dignity is defined in a new way which is influenced by the generic elements: life history, health history, individuality and a stroke. Stroke patient’s dignity is realized through five specific types on realization: person related dignity type, control related dignity type, independence related dignity type, social related dignity type and care related dignity type. The theory points out possible special characteristics of stroke patients’ dignity in control related dignity type and independence related dignity type. Before implementing the theory, the relation between the core category, generic elements and specific types on realization needs to be studied further.

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Floral nectar is thought to be the primary carbohydrate source for most dipteran species. However, it has been shown that black flies (Burgin & Hunter 1997 a,b,c), mosquitoes (Foster 1995; Burkett et al. 1999; Russell & Hunter 2002), deer flies (Magnarelli & Burger 1984; Janzen & Hunter 1998; Ossowski & Hunter 2000), horse flies (Schutz & Gaugler 1989; Hunter & Ossowski 1999) and sand flies (MacVicker et al. 1990; Wallbanks et al. 1990; Cameron et al. 1992, 1995; Schlein & Jacobson 1994, 1999; Hamilton & EI Naiem 2000) feed on homopteran honeydew as well as floral nectar. Prior to 1997 floral nectar was thought to be the main source of carbohydrates for black flies. However, Burgin & Hunter (1 997a) demonstrated that up to 35% of black flies had recently consumed meals of homo pte ran honeydew. This information has necessitated a re-assessment of many life history aspects of black flies. Attempts are being made to examine the effects of nectar versus honeydew on black fly fecundity and parasite transmission (Hazzard 2003). Recently, Stanfield and Hunter (unpublished data) have shown that in female black flies, honeydew sugars produce flights of longer distance and duration than do nectar sugars. This thesis examines two aspects of black fly biology as it relates to sugar meal consumption. First, the effects of honeydew and nectar on black fly longevity are examined. Second, the proximate causation behind longer flight performances in honeydew-fed flies will be examined. The comparison between these two sources is important because nectar is composed of mainly simple sugars (monosaccharides and disaccharides) whereas honeydew is composed of both simple and complex sugars (including trisaccharides and tetrasaccharides ).

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The purpose of this study was to provide an in-depth, life history examination of the leadership qualities of the President of a for-profit sport organization and explore this individual's leadership development within the framework of the Authentic Leadership Development Model (ALDM). A series of semi-structured interviews was conducted, including interviews with the President, three employees within the organization, and three individuals as selected by the President who attested to her authenticity and lifehistory. As well, observations for a period of three months were used to create a lifehistory of the President and determine if she was aligned with the ALDM. Creating a lifehistory of the President allowed the researcher to outline the story of her life up until the conclusion of the study. The narrative case study of the female President of a for-profit sport organization provided a glimpse into the life of a person whose values, beliefs, and actions aligned. The major findings of this study suggested that the President displayed characteristics similar to those identified as outcomes of the ALDM model.

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The diary was written when Beam was nineteen years old. Her father, Charles O. Beam, was a dentist with an office on Queen Street in St. Catharines. Winnie Beam lived with her father and mother, Emma, on Ontario Street, St. Catharines.

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Ce mémoire s’intéresse aux récits des ex-combattants des groupes paramilitaires Autodéfenses unies de Colombie sur leur participation au conflit armé. Ces narrations, construites dans un contexte de réintégration à la société, permettent de réfléchir à la construction de la vérité par les ex-combattants dans les contextes post-conflit. Nous avons analysé les histoires de vie de 18 ex-combattants qui participaient au Programme de réintégration à la vie civile à Bogota. Nos interviewés ont adopté une position de victimes, en élaborant des discours justificateurs visant à se déresponsabiliser. Ces discours montrent une normalisation de la violence qui revient à la notion de « banalité du mal » d’Hannah Arendt. Nos interviewés ont employé plusieurs rhétoriques des groupes paramilitaires afin de justifier la violence. Ces rhétoriques font partie de la construction psychologique de l’ennemi par les groupes et elles invitent à analyser le rôle du langage dans la construction d’une culture paramilitaire. Néanmoins, certains interviewés ont condamné la violence exercée par leur groupe. Nous avons observé qu’il existe plusieurs interprétations de la manière dont nos interviewés disaient avoir réagi aux contextes de violence de masse, ce qui nous a amenés à réfléchir aux notions de culpabilité morale et juridique.

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Thèse de doctorat réalisée dans le cadre d'une cotutelle entre l'Université de Montréal et l'École des Hautes Études en Sciences Sociales, Paris

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L’évaluation économique en santé consiste en l’analyse comparative d’alternatives de services en regard à la fois de leurs coûts et de leurs conséquences. Elle est un outil d’aide à la décision. La grande majorité des décisions concernant l’allocation des ressources sont prises en clinique; particulièrement au niveau des soins primaires. Puisque chaque décision est associée à un coût d’opportunité, la non-prise en compte des considérations économiques dans les pratiques des médecins de famille peut avoir un impact important sur l’efficience du système de santé. Il existe peu de connaissances quant à l’influence des évaluations économiques sur la pratique clinique. L’objet de la thèse est de comprendre le rôle de l’évaluation économique dans la pratique des médecins de famille. Ses contributions font l’objet de quatre articles originaux (philosophique, théorique, méthodologique et empirique). L’article philosophique suggère l’importance des questions de complexité et de réflexivité en évaluation économique. La complexité est la perspective philosophique, (approche générale épistémologique) qui sous-tend la thèse. Cette vision du monde met l’attention sur l’explication et la compréhension et sur les relations et les interactions (causalité interactive). Cet accent sur le contexte et le processus de production des données souligne l’importance de la réflexivité dans le processus de recherche. L’article théorique développe une conception nouvelle et différente du problème de recherche. L’originalité de la thèse réside également dans son approche qui s’appuie sur la perspective de la théorie sociologique de Pierre Bourdieu; une approche théorique cohérente avec la complexité. Opposé aux modèles individualistes de l’action rationnelle, Bourdieu préconise une approche sociologique qui s’inscrit dans la recherche d’une compréhension plus complète et plus complexe des phénomènes sociaux en mettant en lumière les influences souvent implicites qui viennent chaque jour exercer des pressions sur les individus et leurs pratiques. L’article méthodologique présente le protocole d’une étude qualitative de cas multiples avec niveaux d’analyse imbriqués : les médecins de famille (niveau micro-individuel) et le champ de la médecine familiale (niveau macro-structurel). Huit études de cas furent réalisées avec le médecin de famille comme unité principale d’analyse. Pour le niveau micro, la collecte des informations fut réalisée à l’aide d’entrevues de type histoire de vie, de documents et d’observation. Pour le niveau macro, la collecte des informations fut réalisée à l’aide de documents, et d’entrevues de type semi-structuré auprès de huit informateurs clés, de neuf organisations médicales. L’induction analytique fut utilisée. L’article empirique présente l’ensemble des résultats empiriques de la thèse. Les résultats montrent une intégration croissante de concepts en économie dans le discours officiel des organisations de médecine familiale. Cependant, au niveau de la pratique, l'économisation de ce discours ne semble pas être une représentation fidèle de la réalité puisque la très grande majorité des participants n'incarnent pas ce discours. Les contributions incluent une compréhension approfondie des processus sociaux qui influencent les schèmes de perception, de pensée, d’appréciation et d’action des médecins de famille quant au rôle de l’évaluation économique dans la pratique clinique et la volonté des médecins de famille à contribuer à une allocation efficiente, équitable et légitime des ressources.